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Georgy Adelson-Velsky - one of the first Soviet programmers (together with [[Alexander Kronrod]], [[Alexander Brudno]], [[Mathematician#Landis|Evgenii Landis]] and others). He was occupied by the programs, connected with [https://en.wikipedia.org/wiki/Nuclear_physics nuclear physics] at [[Institute of Theoretical and Experimental Physics|ITEP]], where he devised many algorithms which became classical. Especially the equilibrium binary trees, which in the entire world are called [https://en.wikipedia.org/wiki/AVL_tree AVL trees] after the names of the authors - Adelson-Velsky and Landis. After short-term teaching at [[Moscow State University|MGU]] he worked at IPU and VNIISI (All-Union Scientific Research Institute of Sanitary Testing) on discrete algorithms, [https://en.wikipedia.org/wiki/Network_planning_and_design network planning] and [[Artificial Intelligence|artificial intelligence]]. He now lives in Israel and works at [https://en.wikipedia.org/wiki/Technion_%E2%80%93_Israel_Institute_of_Technology Technion] on [https://en.wikipedia.org/wiki/NP_%28complexity%29 NP problems of complete tasks].

The following anecdote sheds some light on how things were done in the [https://en.wikipedia.org/wiki/Soviet_Union USSR]. Shortly after the "[https://en.wikipedia.org/wiki/Iron_Curtain iron curtain]" fell in 1990, an American and a Russian, who had both worked on the development of weapons, met. The American asked: "When you developed the [https://en.wikipedia.org/wiki/Soviet_atomic_bomb_project Bomb], how were you able to perform such an enormous amount of computing with your weak computers?". The Russian responded: "We used better algorithms."

This was really so. Russia had a long tradition of excellence in Mathematics. In addition, the usual Soviet method for attacking hard problems was to combine pressure from the authorities with people's enthusiasm. When [https://en.wikipedia.org/wiki/Joseph_Stalin Stalin] decided to develop the Bomb, many bright mathematicians, e.g. [[Mathematician#Gelfand|Israel Gelfand]] and my first Math teacher, [[Alexander Kronrod]], put aside their mathematical studies and delved deeply into the novel area of computing. They have assembled teams of talented people, and succeeded. The teams continued to grow and work on the theory of computing.

The supervisor of my M.Sc. thesis was Georgy Adelson-Velsky, one of the fathers of Computer Science. Among the students in his group were M. Kronrod (one of the future "[https://en.wikipedia.org/wiki/Method_of_Four_Russians Four Russians]", i.e. the four authors of <ref>[[Vladimir Arlazarov]], [http://www.cs.bgu.ac.il/~dinitz/ E. A. Dinic], [http://oxfordindex.oup.com/view/10.1093/acref/9780199234004.013.2826 M. A. Kronrod], [https://zbmath.org/authors/?q=ai:faradzhev.i-a I. A. Faradzhev] ('''1970'''). ''On economical construction of the transitive closure of a directed graph''. [https://en.wikipedia.org/wiki/Proceedings_of_the_USSR_Academy_of_Sciences Doklady Akademii Nauk] (in English) 194, No. 11, 1209-1210</ref>), A. Karzanov (the future author of the O(n3) [https://en.wikipedia.org/wiki/Maximum_flow_problem network flow algorithm] <ref>[http://alexander-karzanov.net/ Alexander V. Karzanov] ('''1974'''). ''[http://www.researchgate.net/publication/230837862_Determining_the_maximal_flow_in_a_network_by_the_method_of_preflows Determining the maximal flow in a network by the method of preflows]''. [https://en.wikipedia.org/wiki/Proceedings_of_the_USSR_Academy_of_Sciences Soviet Mathematics - Doklady], Vol. 15, No. 1</ref>) and other talented school pupils of A. Kronrod. This was in 1968, long after the Bomb project completed. The work on the foundations of the chess program "[[Kaissa]]", created by members of A. Kronrod's team under guidance of Adelson-Velsky, was almost finished; "Kaissa" won the [[WCCC 1974|first world championship]] in 1974. Adelson-Velsky's new passion became discrete algorithms, which he felt had a great future.

The fundamental contribution of Adelson-Velsky to Computer Science was [https://en.wikipedia.org/wiki/AVL_tree AVL-trees]. He (AV) and [[Mathematician#Landis|Evgenii Landis]] (L) published a paper about AVL-trees in early 60's, consisting of just a few pages. Besides solving an important problem, it presented a bright approach to data structure maintenance. While this approach became standard in the USSR, it was still not known in the West. No reaction followed their publication during a couple of years, until another paper, 15 pages long, was published by a researcher, which understood how AVL-trees work and explained this to the Western community, in its language. Since then, AVL-trees and the entire data structure maintenance approach became a corner-stone of Computer Science.

[[Timeline#1963|1963]] - beginning of the works on the first Soviet chess program in the [[Institute of Theoretical and Experimental Physics]] (ITEP) in the laboratory under [[Alexander Kronrod|Alexander Kronrod's]] management. The first authors - Georgy Adelson-Velsky, [[Vladimir Arlazarov]], [[Alexander Bitman]], [[Alexander Zhivotovsky]], [[Anatoly Uskov]], A. Leman, M. Rozenfeld.

[[Timeline#1967|1967]] - first international match of chess programs. Competed the program ITEP and the program of [[Stanford University]], made under the management [[John McCarthy]]. McCarthy is famous fact that in 1952 on the beach in San Diego together with [[Alan Turing]] devised the word combination of "Artificial Intelligence", and fact that he is the author of the language Lisp - the first programming language, specially created for the tasks in the problems of artificial intelligence. Regulations of the [[Stanford-ITEP Match|match]] - four games. From the side of Stanford played one and the same version, from the ITEP side - two, which were being distinguished by the depth of search. Moves were transferred by the telegraph once a week (this to those- that times from "yadernogo" institute!). Match continued entire year and ended with the score the 3:1 in favor of ITEP.

[[Timeline#1969|1969]] - a letter in support of mathematician [https://en.wikipedia.org/wiki/Alexander_Esenin-Volpin Esenin-Volpin] (son of [https://en.wikipedia.org/wiki/Sergei_Yesenin poet]) and his incorrect psychiatric confinement, among others signed by [[Alexander Kronrod]] and Georgy Adelson-Velsky. As a result, the laboratory was disbanded and its major portion under [[Vladimir Arlazarov|Vladimir Arlazarov's]] management, but without Kronrod, after a certain time he settled in [[Institute of Control Sciences]] (ICF).

[[Timeline#1970|1970]] - the mechanic mathematical department of [[Moscow State University|MGU]] finished the entire group of the students of [[Alexander Kronrod]] and Georgy Adelson-Velsky, that was being occupied in the famous seminar for discrete algorithms. Sums of the seminar:* <code>For Georgy Adelson-Velsky it was forbidden to teach in MGU</code>

Adelson-Velsky, an extremely capable and animated scientist and a real pleasure to meet, generally led our technical discussions. His eyes seemed to glisten with enthusiasm when he spoke. Discussions centered around probabilistic analyses of various aspects of the [[Minimax|minimax]] algorithm and [[Parallel Search|parallel search]] of chess trees. Our first joint seminar on [[Alpha-Beta|alpha-beta]] analysis and the impact of computer technology was attended by about thirty people, including [[Mathematician#LVKantorovich|Leonid Kantorovich]], winner of the 1975 [https://en.wikipedia.org/wiki/Nobel_Prize_in_Economics Nobel Prize in Economics] for his work on [https://en.wikipedia.org/wiki/Linear_programming linear programming].